Method of making can bodies



June 6, 1944. J RQJO 2,350,824

METHOD OF MAKING CAN BODIES Filed May 18, 1942 r I 1' W, Q 1% I;

9 r I Z Patented June 6, 1944 RIETHOD OF MAKING CAN BODIES Jeslis MiguelRojo, Habana, Cuba, assig'nor to Continental Can Company, Inc., acorporation of New York Application May 18, 1942, Serial No. 443,523

I Claim.

forming body flanges for the attachment of can ends, it has beencustomary to subject the formed can body to the action of a flange diewhich is shaped so as to outwardly expand and outwardly roll the edgeportions of the can body in the region of the lap sections. This actionproduces an outwardly curved flange which lies in a plane substantiallyat right angles to the longitudinal axis of the can body. In followingthis procedure, considerable diificulty has been encountered inproducing a sufficiently tight joint at the lap sections because of thedouble thickness of metal at these points and also because there is nosupport at the outside of the can body in the flanging operation. Thus,the lap sections tend to 'separate or open so that leakage is liable tooccur.

The principal object of the present invention is to produce asufliciently tight seam in can bodies of the type referred to above.

Another object of the invention is to provide a method of forming canbodies of the above type wherein the lap sections of the solderless sideseam are maintained in tight contact during the flanging operation'so asto produce a suflicientiy tight container.

A further object of the invention is to provide a method of forming canbodies of the above type wherein the body flange in the region of thelap sections is preformed during bumping of the lock seam and prior tocompletion of the body flange under the action of flanging dies.

The above and other objects of the invention will in part be obvious andwill be hereinafter more fully pointed out.

In the accompanying drawing:

Figure 1 is a side elevation of a can body prior to the formation of thebody flanges.

Figure 2 is a side view with the can body in section, showing theposition of the can body between the spline and the bumping iron priorto the bumping operation.

Figure 3 is an enlarged end sectional view of Figure 2.

Figure 4 is a side elevation of the can body after the preforming of thebody flanges in the region of the lap sections.

Figure 5 isa sectional view throughthe spline and showing the formationof the preformed flange portion during bumping of the lock seam.

Figure 6 is an enlarged end sectional view of Figure 5.

Figure 7 is a diagrammatic view showing the completed flanging operationunder the action of a flanging die.

The method of the present invention will be described in connection withthe flanging of a can body having a solderless side seam which includesinterlocking hooks throughout the major portion thereof and lap sectionsat the ends of the side seam. This type of container is well known sothat only brief reference need be made thereto. As shown in Figure 1 ofthe accompanying drawing, thecan body ID has the edges thereof securedtogether by a solderless side seam. This side seam includes interlockinghooks II which form a lock seam. The opposite ends of the side seam areformed by lap sections l2. The can body is preferably cylindrical inshape and is formed in the usual manner about a horn and the hooks IIare interlocked after which they are bumped into tight and intimatecontact with each other. This is accomplished by placing the interlockedhooks on a spline II! which is carried by the horn (not shown) in theusual manner.

The spline I3 is provided with the usual recess M for receiving theinterlocking hooks ll during the bumping operation. The spline is alsoprovided with outwardlyprojecting blocks l5 which are longitudinallyspaced along the recess l4 so that the hooks ll fit between the blockswith the lap sections l2 resting on the blocks, as particularly shown,in Figure 2 of the accompanying drawing. In the position of Figure 2,the can body is in position for the bumping operation which isaccomplished by a bumping iron it which has a rib portion l'lterminating at the ends of the hooks II and within the blocks l5 on thespline.

As the bumping iron I 6 is moved toward the spline for bumping the hooksll forming the lock seam, the outer surface of the rib I! will force thelock seam into the recess M, as shown in Figures 5 and 6. The ends Ha ofthe rib I! provide shoulders which fit within the blocks I5 during thebumping operation so that the lap sections l2 are forced outwardly andin tight contact with one another between the blocks l5 and theshoulders Ila on the bumping iron. 7 This position oi! the can body isshown in Figures 5' and 6 and this bumping action results in the peiormine of limited flange portions It in the region of the lapsections, as shown in Figure 4. Thus, the body flanges to which the canends are se t red are partially preformed during the lock s am bumpingoperation so that the lap sections II are maintained in tight contactwith one another.

After the bumping and partial flanging operation, the can body issubjected to the action of a flange die I! (Figure 7) so that the bodyflange 20 is completed around the edges or the can body and thiscompleted body flange 20 forms a continuation of the preformed flangeportion From the foregoing description, it will be seen that the presentinvention provides an efllcient method of forming sheet metal can bodieswith The initla1 formation of body flange at the lap sections serves tomaintain these lap sections in tight contact with each other in order toprevent leakage when the can ends are secured thereto. This preformingof a part of the body flange at the lap sections is accomplished duringbumping of the lock section of the side seam and the bumping iron andblocks on the spline are shaped to cooperate with one another inmaintaining this tight contact between the flanged lap sections. Afterthis initial preiorming of a part or the body flange, the formed canbody is subjected to the action or conventionalwflanflm dies whichcomplete the formation oi-Ethe body flanges as continuations oi thepreformed flange portions at the lap sections. He'rtoiore, the lapsections tended to separate or open up during the flanging operation sothat leakage was apt to occur but with the present method, the lapsections, are maintained in tight contact with one another during theinitial flanging operation and the final flanging operation does notdisturb the previously flanged lap sections.

It is to be clearly understood that the method can be carried out withminor variations without distinguishing from the scope of the inventionas set forth in the appended claim.

I claim:

The method oi! forming a sheet metal can body having a solderless sideseam including interlocking hooked portions and lapping portions,comprising shaping the can body and engaging the hooked portions,subjecting said engaged hooked portions to pressure for interlocking thesame in a tightly-formed seam, simultaneously pressing the lappedportions of the side seams into contact, one with the other, and curvingsaid contacting lapped portions outwardly to form a partial flange andthen simultaneously die-shaping the body wall and the partially formedflange into a completed seaming flange extending all away around the end01 the can bo y.

msfis MIGUEL ROJO.

